A number of digital cruise control systems have been implemented in the automotive industry. One general type of system includes a control activated by the driver by means of which the driver first accelerates up to the desired cruise speed and then enters that speed which he has attained by activating the control. This system stores that speed as a reference, and maintains the auto at that speed, the cruise speed, by detecting deviations from the cruise speed and correspondingly accelerating or decelerating the automobile. In some systems, if the brake is activated, the accelerator mechanism is released from control of the cruise control system, but the reference cruise speed is still stored. After the braking operation is over, the driver may activate the cruise control system to cause the automobile to accelerate back up to the reference cruise speed. Such cruise control systems have been utilized complex circuitry and have been quite costly. Simpler, more reliable, less complex and less costly cruise control, velocity control and acceleration control systems are needed.